Retaining means for drafting rollers



June 19, 1956 w. STAHLECKER EFAL 2,750,634

RETAINING MEANS FOR DRAFTING ROLLERS Filed Nov. 50, 1953 3 Sheets-Sheet 1 IHVENTORS,

WILHE'LM STAHLEck'ER AND HANS ScHuRR June 19,1956

Filed Nov. 50, 1953 W. STAHLECKER ETAL RETAINING MEANS FOR DRAFTING ROLLERS 3 Sheets-Sheet 2 INVE'HTDRS.

MLHELM s-mHLE wER AND HANS S HuRR June 19, 1956 w. STAHLECKER ETAL 2,750,634

RETAINING MEANS FOR DRAFTING ROLLERS Filed Nov. 30, 1953 3 Sheets-Sheet 5 mvsm'oR r NJLHEL-m STAHLECKER Pmo HMS R United States Patent RETAINING MEANS FOR DRAFTING ROLLERS Wilhelm Stahlecker, Tubingen, and Hans Schurr, Sussen, Germany Application November 30, 1953, Serial No. 395,242

Claims priority, application Germany December 1, 1952 8 Claims. (Cl. 19-142) The present invention relates to Spinning machines, and more particularly to retaining or locking means for removably securing the drafting or pressure rollers on their spindles.

In spinning frames, the sliver or strand of fiber is generally drafted between several pairs of pressure or drafting rollers, each pair of which revolves slightly faster than the previous pair and is provided with suitable weighting or tensioning means. Usually, at least one drafting roller of each pair is provided with a coating, sheath, or cover of resilient material, such as felt, leather, rubber, cork, plastic, or the like. As these covers wear out relatively quickly under the pressure of the rollers and the tension of the fiber passing therethrough, it has been found advisable to make them more easily removable from their supporting spindles by providing them on separate sleeves which, in turn, are placed upon the spindles or suitable bearings thereon.

It is the object of the present invention to devise simple and inexpensive means for easily exchanging such cover sleeves on the bearings supporting them on the drafting spindles, and for securely retaining them on such bearings while in use.

Another object of the invention is to provide means of the type described which, although permitting easy removal of the cover sleeves from the bearings, render the replacement thereof more difficult, so as to prevent more inexperienced or careless operators from placing the wrong type of sleeve or one of a wrong diameter upon the ball or roller bearings on the respective drafting spindle, and to insure that such replacement, although extremely simple and easy, will only be carried out by a more experienced or reliable person designated for such purpose.

A feature of the invention for attaining these objects consists in providing the outer race of the bearing which supports the drafting roller with a suitable annular groove, and in a simple annular spring of such size and configuration so as to fit loosely in such groove and, when the cover sleeve is placed on the bearing, to press against the inner Wall of the cover sleeve to retain the latter on the bearing and prevent it from sliding in axial direction of the spindle.

Further objects, features, and advantages of the present invention will appear from the following detailed description thereof and the annexed drawings, in which Fig. 1 shows, partly in section, a drafting spindle with the retaining spring according to the invention provided on the roller or ball bearings ready for placing the cover sleeve thereon;

Fig. 2 is a cross section along line A-A of Fig. 1;

Fig. 3 is a longitudinal section through a cover sleeve;

Fig. 4 illustrates the method of inserting the ball bearing into the cover sleeve by manually compressing the retaining spring;

Fig. 5 shows the drafting spindle with the bearing part- 2,750,634 Patented June 19, 1956 1y inserted in the cover sleeve before compressing the retaining spring;

Fig. 6 is another partial section of the cover sleeve fully placed upon thebearing and ready for operation with the retaining spring in a locking condition;

Fig. 7 shows the ball bearing of the drafting spindle according to Fig. 1 partly inserted in a cover sleeve which is provided with a shoulder which prohibits the compression of the retaining spring by hand and requires the use of a special tool for fully inserting the bearing into the cover sleeve;

Fig. 8 is a perspective view of the drafting spindle with a cover sleeve of the type and in the position as shown in Fig. 7 in a suitable mounting device for holding the cover sleeve while the retaining spring is compressed by means of a pair of pliers or a tool specially designed for that purpose to permit the bearing on one end of the spindle to be fully inserted into the cover sleeve;

Fig. 9 shows the cover sleeve according to Figs. 7 and 8 placed upon the bearing with the retaining spring in a locking position therein; while Fig. 10 shows the same cover sleeve partly removed from its bearing.

Referring to the drawings, the retaining springs are made of fiat spring steel bent to an annular shape with an open portion as shown in Fig. 2, and of a width and strength so as to permit it to be radially compressed by hand to fit within an annular groove 2 which is provided in the outer race 4 of a roller or ball bearing 3 on the drafting spindle 10. The retaining spring 1, when released, is preferably made of a size considerably exceeding the diameter of the groove 2 and substantially cor responding to the inner diameter of a recessed portion 51 of the cover sleeve 5 which, in the embodiment of the invention shown especially in Figs. 3 to 6, has a gradually beveled portion 7 toward the smaller inside diameter of the sleeve 5, so as to further compress the spring 1 automatically when pushed into the sleeve 5 after it has been initially compressed by hand as shown in Fig. 4 and fitted into the shoulder portion 51. When fully inserted into the cover sleeve 5, the spring 1 is centered by the inner wall thereof and pressed tightly against the same, its inner diameter then, however, still exceeding the size of the diameter of the groove 2 in the outer race 4 of the bearing 3, as shown particularly in Fig. 6. The cover sleeve 5, which fits loosely upon the outer race 4 so as to permit a certain radial play thereon, is thus able to rotate relative to the outer race 4 substantially without friction, thereby still further improving the bearing qualities provided by the roller or ball bearing 3.

The cover sleeves 5, shown in Figs. 2 to 6, which usually are provided with a coating, sheath, or cover 5 of resilient material, such as felt, leather, rubber, cork, plastic, or the like, are designed so as to permit them not only to be easily placed upon the bearing 3 but also to be just as easily removed therefrom if, for example, the coatings or covers 5 are damaged and require replacement, or for any other purpose. However, even in the best conducted spinning mill it may occur that less experienced, careless, or inattentive operators will attempt to place upon one particular drafting spindle a cover sleeve carrying the wrong type of cover or one of a diameter intended for a different spindle and not suited for this spindle. Since even very small differences in the diameter of the drafting rollers, especially when provided with one of the modern, rather hard, plastic covers, considerably affect the quality of the yarn, some spinning mills have proceeded to secure the cover sleeves on the drafting spindles so as to prevent the operator from exchanging them of her own accord.

Such unauthorized exchange of the cover sleeves by the operator herself will be prevented by the embodiment of the invention shown in Figs. 7 to 10, wherein the cover sleeve may be easily withdrawn from the drafting spindle by such operator, but cannot be replaced by her, since the beveled portion 7 shown in the previous drawings, which automatically compresses the spring 1 to the inner diameter of the outer race 4 of the bearing 3 when the sleeve 5 is pushed thereon, is replaced by a shoulder 7'. Although the annular spring ll within the groove 2 may be easily compressed by hand to insert it with the bearing 3 into the recessed portion 51 until th spring 1 is almost completely within the sleeve, it will finally abut against the shoulder 7 and be thereby prevented from further inward movement. Unless the operator of the machine is herself authorized to use a suitable appliance for further compressing the spring 1 for fully inserting the bearing 3 into the cover sleeve 5, she will have to call a foreman or supervisor to do it for her. For this purpose, a suitable pair of pliers or similar tool 9, such as shown, for example, in Fig. 8, may be applied upon the narrow projecting portion 8 of the spring 1 to compress the spring into the groove 2 sufiiciently to slip past the shoulder 7. In order to facilitate such insertion of the bearing 3 with the spring ll thereon into the cover sleeve 5, a suitable mounting fixture ll may be provided, as shown in Fig. 8.

Even though prevented by the shoulder 7 from reinserting the bearing 3 completely into the sleeve 5, the operator herself may withdraw the sleeve sufficiently, as shown in Fig. 7, to remove any foreign matter which might collect during the operation in the space 12 intermediate the cover sleeve 5 and the spindle 1t), and thereafter push the sleeve again fully upon the bearing 3.

While we have described our invention with reference to several preferred embodiments thereof, we wish it to be expressly understood that our invention is in no way limited to the details of such embodiments but is capable of numerous modifications within the scope of the appended claims. For example, the retaining spring as well as the groove in the outer race of the bearing in which the spring is inserted may be made of various difierent shapes.

What we claim is:

1. For use in a spinning machine, in combination, a spindle, a bearing race rotatable on said spindle, a roller comprising an outer sleeve having an inner elongated ungrooved cylindrical face portion of constant diameter, and means removably securing said sleeve on said race, said means comprising a substantially cylindrical leaf spring of resilient sheet material having opposite ends located adjacent each other to permit compression of the spring, said spring being loosely mounted on said race so as to permit radial play of said spring relative to said race, means on said race to retain said spring in a fixed axial position on said race, said spring being adapted to be compressed when said race is inserted into said sleeve and then to press with its entire width against said inner ungrooved cylindrical face portion of said sleeve to retain the same in a fixed axial position.

2. For use in a spinning machine, in combination, a spindle, a bearing race rotatable on said spindle, a roller comprising an outer sleeve having a smooth, uninterrupted inner ungrooved cylindrical face portion, means for removably securing said sleeve on said race, said means comprising a substantially cylindrical spring of flat sheet material of a thickness substantially less than the width thereof and having opposite ends adjacent each other to permit compression of said spring, the width of said spring being substantially less than that of said inner ungrooved face portion of said sleeve and said spring being loosely mounted on said race, and means on said race to retain said spring when compressed in a fixed axial position on said race, said sleeve having an inner annular recessed portion at one end thereof of a diameter corresponding substantially to that of the spring when partly compressed on said race so as to permit easy insertion of said spring into said recessed portion, and a beveled portion connecting said recessed portion with said inner ungrooved cylindrical face portion of said sleeve for automatically compressing the spring when said race is further inserted into said sleeve, said spring then being adapted to press with its entire outer surface against said inner ungrooved face portion of said sleeve to retain the same rotatably on said race but in a fixed axial position thereon.

3. For use in a spinning machine, in combination, a spindle, a bearing race rotatable on said spindle, a roller comprising an outer sleeve having a smooth, inner, uninterrupted, cylindrical face portion, means for removably securing said sleeve on said race, said means comprising a substantially cylindrical leaf spring of flat sheet material of a thickness substantially less than the width thereof and having opposite ends adjacent each other to permit compression of said spring, said spring being loosely mounted on said race, and means on said race to retain said spring when compressed in a fixed axial position on said race, said sleeve having next to said inner face portion an inner annular recessed end portion of a diameter corresponding to that of the spring when partly compressed on said race so as to permit easy insertion of said spring into said recessed portion, said recessed portion being of a width slightly less than the width of said spring so that, when the latter is inserted in said recessed portion, a narrow portion of said spring still projects from said sleeve, said recessed portion terminating toward the inside of said sleeve in a shoulder preventing full insertion of said spring without the aid of a special tool for compressing said narrow portion of said spring to the inner diameter of said inner face portion of said sleeve, said spring when fully inserted in said sleeve pressing with the entire width of its outer surface against said inner face portion of said sleeve to retain the same rotatably on said spindle but in a fixed axial position thereon.

4. For use in a spinning machine, in combination, a spindle; a bearing race rotatably carried by said spindle; an elongated, substantially cylindrically curved leaf spring of resilient sheet material, having a width more than three times greater than its thickness and having opposite adjacent free ends permitting contraction and expansion of said leaf spring, located about said bearing race; means on said bearing race mounting said spring thereon in a predetermined axial position for free radial contraction and radial expansion outwardly beyond the outer surface of said race; a roller sleeve having a smooth uninterrupted inner cylindrical ungrooved face portion of constant diameter and a width substantially greater than that of said spring and of a diameter greater than that of said bearing race and smaller than that of the unstressed spring, said sleeve being located about said bearing race and said spring bearing with its entire outer surface against said inner ungrooved face portion of said sleeve to retain the latter in a predetermined axial position on said bearing race.

5. For use in a spinning machine, in combination, a spindle; a bearing race rotatably carried by said spindle; an elongated, substantially cylindrical curved leaf spring of resilient sheet material, having a width more than three times greater than its thickness and having opposite adjacent free ends permitting contraction and expansion of said leaf spring, located about said bearing race; means on said bearing race mounting said spring thereon in a predetermined axial position for free radial contraction and radial expansion outwardly beyond the outer surface of said race; a roller sleeve having a smooth uninterrupted inner ungrooved cylindrical face portion of constant diameter and a width substantially greater than that of said spring and of a diameter greater than that of said bearing race and smaller than that of the unstressed spring, said sleeve being located about said bearing race and said spring bearing with its entire outer surface against said ungrooved inner face portion of said sleeve to retain the latter in a predetermined axial position on said bearing race, said sleeve being open at at least one end thereof and having at said one end an inner annular portion of a diameter greater than that of said inner cylindrical face portion of said sleeve and located adjacent said latter face portion, whereby said spring may first be partly compressed and placed in said inner annular portion of said sleeve before being further compressed and moved into engagement with said ungrooved inner face portion of said sleeve.

6. For use in a spinning machine, in combination, a spindle; a bearing race rotatably carried by said spindle; an elongated, substantially cylindrically curved leaf spring of resilient sheet material, having a width more than three times greater than its thickness and having opposite adjacent free ends permitting contraction and expansion of said leaf spring, located about said bearing race; means on said bearing race mounting said spring thereon in a predetermined axial position for free radial contraction and radial expansion outwardly beyond the outer surface of said race; a roller sleeve having a smooth uninterrupted inner ungrooved cylindrical face portion of a width substantially greater than that of said spring and of a diameter greater than that of said bearing race and smaller than that of the unstressed spring, said sleeve being located about said bearing race and said spring bearing with its entire outer surface against said inner ungrooved face portion of said sleeve to retain the latter in a predetermined axial position on said bearing race, said sleeve being open at at least one end thereof and having at said one end an inner annular portion of a diameter greater than that of said inner cylindrical face portion of said sleeve and located adjacent said latter face portion, whereby said spring may first be partly compressed and placed in said inner annular portion of said sleeve before being further compressed and moved into engagement with said inner ungrooved face portion of said sleeve, said inner annular portion of said sleeve being joined to said inner cylindrical face portion thereof by a beveled inner surface portion of said sleeve so that said spring may be manually compressed while said sleeve is manually moved axially onto said bearing race.

7. For use in a spinning machine, in combination, a spindle; a bearing race rotatably carried by said spindle; an elongated, substantially cylindrically curved leaf spring of resilient sheet material, having a width more than three times greater than its thickness and having opposite adjacent free ends permitting contraction and expansion of said leaf spring, located about said bearing race; means on said bearing race mounting said spring thereon in a predetermined axial position for free radial contrac tion and radial expansion outwardly beyond the outer surface of said race; a roller sleeve having a smooth uninterrupted inner cylindrical face portion of a width substantially greater than that of said spring and of a diameter greater than that of said bearing race and smaller than that of the unstressed spring, said sleeve being located about said bearing race and said spring hearing with the entire width of its outer surface against said inner face portion of said sleeve to retain the latter in a predetermined axial position on said bearing race, said sleeve being open at at least one end thereof and having at said one end an inner annular portion of a diameter greater than that of said inner cylindrical face portion of said sleeve and located adjacent said latter face portion, whereby said spring may first be partly compressed and placed in said inner annular portion of said sleeve before being further compressed and moved into engagement with said inner face portion of said sleeve, said inner annular portion of said sleeve being joined to said inner cylindrical face portion by a shoulder in said sleeve having an annular side face directed toward said one end of said sleeve and located in a plane substantially normal to the spindle axis, whereby said spring cannot be moved into said sleeve beyond said shoulder without the use of a tool.

8. For use in a spinning machine, in combination, a bearing race adapted to be rotatably carried by a spindle and being formed in its outer surface with an annular groove extending about the axis of said race; a leaf spring located loosely in said annular groove to be retained thereby in a predetermined axial position on said race, said spring extending almost completely about said race and having a pair of opposite free ends located adjacent each other so that said leaf spring may contract and expand radially, said spring in its unstressed condition being located substantially along a cylinder of a diameter greater than that of said race; and a roller sleeve coaxial with said race and located thereabout, said sleeve having an inner smooth uninterrupted annular ungrooved face portion of constant diameter wider than said spring, of a diameter smaller than that of said cylinder and larger than that of said race, and engaged by said spring at the entire width of the outer surface thereof.

References Cited in the file of this patent UNITED STATES PATENTS Wardwell Feb. 19, 1924 

